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Updated: Feb 15, 2026

A High-performance Liquid Chromatography Measurement of Kynurenine and Kynurenic Acid: Relating Biochemistry to Cognition and Sleep in Rats
Published on: August 19, 2018
Kynurenic acid accumulation underlies learning and memory impairment associated with aging
Mihir Vohra1, George A Lemieux1, Lin Lin1
1Department of Physiology, University of California at San Francisco, San Francisco California 94158, USA.
Abstract:
A general feature of animal aging is decline in learning and memory. Here we show that in Caenorhabditis elegans, a significant portion of this decline is due to accumulation of kynurenic acid (KYNA), an endogenous antagonist of neural N-methyl-D-aspartate receptors (NMDARs). We show that activation of a specific pair of interneurons either through genetic means or by depletion of KYNA significantly improves learning capacity in aged animals even when the intervention is applied in aging animals. KYNA depletion also improves memory. We show that insulin signaling is one factor in KYNA accumulation.
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